Hmmm. . .the easiest way I can think of is to turn the circle into a polygon, clip using the rectangle, and then calculate the remaining area.

I would like to find a set of squares that covers the circles on the grid such that there is no overlap of the squares. The set of squares should have minimal area. Some example solutions: ...

Calculate the area of a Circle in Excel. The area of a circle is 3.14*(radius*radius). To create the formula in Excel, I could suggest the exponential function however, ...